The present invention relates to a method and device for linked gaming. More specifically, the present invention is a method and device for issuing progressive bonuses at linked gaming machines.
Players gamble to win and to be entertained. Thus, it is well known in the gambling industry that one of the best ways to attract and retain players is to make the player believe that he has a better chance of winning or that, if successful, he could win more. It is also known that players will tend to play the more exciting and entertaining games. Two methods which utilize this knowledge are progressive jackpots and bonuses.
In a progressive jackpot system, several interconnected gaming machines each contribute a portion of the wagers received by the gaming machine to a progressive jackpot. Because several gaming machines contribute to the progressive jackpot, the jackpot can grow large. Players place wagers and play a primary game at the interconnected gaming machines in a conventional fashion, such as by spinning the reels of a slot machine or by playing hands of video poker. The progressive jackpot is awarded when a player at one of the interconnected gaming machines obtains a predetermined jackpot outcome in the primary game. For example, in Celona (U.S. Pat. No. 5,564,700), a number of gaming machines are linked to a central controller. The central controller computes the amount of the progressive jackpot by adding a predetermined percentage of each wager made at each gaming machine to the progressive jackpot. The jackpot is paid when a player at one of the gaming machines obtains a jackpot-winning outcome. The jackpot is shared among all eligible players regardless of whether the player obtained a jackpot-winning outcome or not, although the player who obtains the jackpot-winning outcome will receive a larger portion of the progressive jackpot.
The drawback of progressive jackpots, however, is that a player at one of the interconnected gaming machines must obtain a jackpot outcome to trigger the progressive jackpot payoff. Consequently, progressive jackpot payoffs are usually rare occurrences and, thus, only marginally contribute to the entertainment value of the game.
By contrast, bonus systems typically pay players without requiring that any player obtain a particular primary game outcome. For example, in Acres et al. (U.S. Pat. No. 5,752,882) several gaming machines are linked to a floor controller. The floor controller selects less than all the linked gaming machines to receive bonus treatment. The floor controller compares wager information from the gaming machines to a fixed bonus minimum and monitors any other bonus criteria specified by the operator such as the time of day, the level of play, the time since the most recent bonus, or the like. When all the criteria are met, the bonus, corresponding to an altered pay table or a designated bonus outcome, is awarded.
The drawback of this system is that the selection of gaming machines to receive bonus treatment is completely random and unrelated to game play. Consequently, the bonus system does not contribute to the entertainment value of the game. Moreover, the criteria for turning on the bonus is a fixed bonus minimum. Thus, the frequency with which the bonus will be turned on will change dramatically depending on the number of players playing at the interconnected machines and the amount each player is wagering. Finally, the bonus minimum criteria is fixed; that is, the bonuses and the bonus pool are not exactly computed. Thus, it is possible that the bonuses will not be inadequately funded.
Thus, there is a need in the art for a progressive bonus system which awards a bonus related to the primary game, but without requiring an immediately preceding primary game outcome, when a dynamic bonus threshold is met.
The present invention is a method and device for distributing a progressive bonus to one or more players playing linked gaming machines. In the method of the present invention, a primary game is provided at a plurality of linked gaming machines. The player makes a wager and plays the primary game in a conventional fashion to obtain an outcome. In addition to the conventional outcomes, a bonus outcome is provided in the primary game. If the player obtains a bonus outcome, a bonus symbol is randomly selected from a plurality of bonus symbols. The gaming machine stores the selected bonus symbol until another bonus outcome is obtained or the gaming machine becomes inactive for a predetermined amount of time. The selected bonus symbol may be displayed at the gaming machine.
A portion of each wager wagered at the linked gaming machines is accrued in an accrual pool. A bonus award between a minimum bonus award and a maximum bonus award is randomly selected and the number of eligible gaming machines in play is determined. A gaming machine is determined to be in play by measuring the time since the most recent wager, or alternatively, measuring the time between wagers. A gaming machine is eligible when the player meets predetermined criteria such as wagering the maximum amount per game. A dynamic bonus threshold is calculated by multiplying the bonus award by the number of eligible gaming machines in play. In other words, the bonus threshold is the total amount that would be paid if every gaming machine in play issued the bonus award. The bonus threshold is compared to the accrual pool. If the accrual pool is less than the bonus threshold, a new bonus award is randomly selected and the bonus threshold is recalculated.
In one embodiment of the present method, when the accrual pool is equal to, or greater than, the bonus threshold, a bonus indicator is randomly selected from a plurality of bonus indicators which correspond to the bonus symbols. The bonus indicator is compared to the bonus symbols at each gaming machine. If at least one gaming machine has selected a bonus symbol corresponding to the selected bonus indicator, the bonus award is issued at all gaming machines displaying a bonus symbol corresponding to the selected bonus indicator. If no gaming machine has selected a bonus symbol corresponding to the selected bonus indicator, the selection process is repeated.
In an alternate embodiment of the present method, when the accrual pool is greater than, or equal to, the bonus threshold, the bonus symbols which have been selected by the gaming machines are detected. A bonus indicator is randomly selected from only those bonus indicators which correspond to selected bonus symbols. This insures that the selected bonus indicator will correspond to at least one selected bonus symbol. The bonus award is issued at all gaming machines which have selected a bonus symbol which corresponds to the bonus indicator.
In the device of the present invention, each of a plurality of gaming machines is electronically linked to a system server. At each gaming machine, a player deposits a wager as a token, coin, or bill. The machine accepts the wager in a manner known in the art. The gaming machine and the system server each includes a computer processor. The gaming machine processor communicates data representing the amount of the wager to the system server which adds a percentage of the wager to the accrual pool. The player plays the primary game in a conventional fashion with winning outcomes being paid and losing outcomes resulting in a loss to the player. If, however, the player obtains certain bonus outcomes in the primary game, the gaming machine processor randomly selects a bonus symbol from a plurality of bonus symbols stored in a first data structure. The gaming machine may include a plasma display which displays the selected bonus symbol. The gaming machine processor stores the selected bonus symbol in a second data structure until the player obtains another bonus outcome or the gaming machine becomes inactive for a pre-determined period of time. The gaming machine processor communicates data representing the outcome of the primary game, and any bonus symbol selected, to the system server.
The system server processor begins the selection process by randomly selecting a bonus award between a maximum and a minimum award. The system server processor also determines the number of eligible gaming machines in play. To determine how many machines are in play, the system server tracks the amount of time elapsed since each gaming machine received a wager, or alternatively, the amount of time elapsed between wagers. To determine eligibility of players, the system server examines the wagering data received from the gaming machines to detect whether the player is wagering the maximum amount per game. The product of the bonus award and the number of eligible gaming machines in play is the dynamic bonus threshold.
The system server processor compares the accrual pool to the bonus threshold. If the accrual pool is less than the bonus threshold, the system server processor randomly re-selects the bonus award and recalculates the bonus threshold. This process repeats until the accrual pool is equal to, or greater than, the bonus threshold.
According to one embodiment of the present device, when the accrual pool meets or exceeds the bonus threshold, the system server processor randomly selects a bonus indicator from a plurality of bonus indicators stored in a third data structure. The bonus indicators correspond to the bonus symbols stored in each gaming machine. The system server detects the bonus symbols, if any, selected by each gaming machine in play. If the bonus indicator selected by the system server matches the bonus symbol selected by at least one gaming machine, the system server communicates an instruction to all gaming machines having a bonus symbol corresponding to the bonus indicator to issue the bonus award. If no gaming machine displays a bonus symbol corresponding to the bonus indicator, the system server begins the selection process anew by randomly selecting a bonus award.
In an alternate embodiment of the present device, when the accrual pool meets or exceeds the bonus threshold, the system server processor detects which bonus symbols have been selected by gaming machines. The system server then selects a bonus indicator from only those bonus indicators which correspond to selected bonus symbols. In other words, the system server selects from a data structure which stores the possible bonus indicators depleted by the bonus indicators which have not had their corresponding bonus symbol selected by a gaming machine. Consequently, the system server processor will always select a bonus indicator corresponding to a bonus symbol selected by at least one gaming machine. The system server sends a signal to issue the bonus award at all gaming machines which have selected the corresponding bonus symbol.
An object of the present invention is to provide a method and device which may reward more than a single player. Another object of the present invention is to reward players based on a continuously active bonus indicia rather than the immediate outcome of the primary game. Yet another object of the invention is to provide a method and device which calculates a dynamic bonus threshold and compares the bonus threshold to the available pool before paying the bonuses to insure that the bonuses are adequately funded.